Protective effect of vitamin E on reduction in colony formation of cultured human cells by bisulfite

Vitamin E stimulates proliferation of experimental oral carcinoma cells in vitro

Vitamin E was found to have a stimulatory effect on the growth in culture of an epidermoid carcinoma cell line derived from chemically induced tumors of hamster buccal pouch. This effect was found to be dose related, with a maximum stimulatory effect at 10 microM. At a concentration of 100 microM, there was an inhibitory effect on both cell turnover and colony formation.

Sulfite oxidase deficiency: a high risk factor in SO2, sulfite, and bisulfite toxicity?

It has been hypothesized that sulfite oxidase deficient persons may be at increased risk to toxicity from SO2 and dietary sulfites widely used for food preservation. Sulfite oxidase is believed to be responsible for the detoxification of SO2 and/or sulfite to sulfate for excretion. Human and animal studies have shown that S-sulfonates, believed to transport sulfite in the blood, are formed in response to exposure to low levels of SO2. Besides its numerous toxic effects, e.g. respiratory impairment, interference with immunological response and oxygen transport and platelet aggregation inhibition, SO2 has the ability to alter DNA during replication causing T . A transitions, chromosome abnormalities and depression of DNA synthesis.

Aggregation patterns of fetal rat brain cells following exposure to X-irradiation

In our search for a simplified in vitro test system to assess the teratogenic effects of physical factors, we studied the effects of total maternal body X-irradiation on aggregation patterns of enzymatically isolated fetal rat brain cells and on ultrastructural aggregate changes. The fetal brain cells were derived from day 14 gestation fetuses of pregnant Sprague-Dawley (CD strain) rats exposed to X-irradiation (25 - 200 R) one hour prior to sacrifice. Notable changes in the cell aggregates following X-irradiation included a reduction in cell aggregate size and an increase in number. The frequency of cell aggregates was higher in the treated than in the control group, and the mean diameter of cell aggregates was inversely related to increasing X-irradiation doses. Transmission electron microscopy revealed in isolated cells features of degenerative process which were similar to those found in intact fetal brain lesions caused by maternal X-irradiation. Furthermore, scanning electron microscopy revealed that inhibition of cell aggregation following X-irradiation could probably be attributed to inhibition of membrane filopodia development and a consequent failure fo cell aggregates to fuse into a greater cell aggregate mass. These results suggest that the membrane factors which influence cell aggregation may be a useful parameter to assess early effects of X-irradiation-induced brain deformity. Presently, the cell aggregation culture system is being further evaluated as a short term test system for environmental teratogens.

Antioxidant-mediated reversal of ultraviolet light cytotoxicity

Several antioxidants were tested for their protective effect in Chinese hamster embryo cell against ultraviolet light (UVL)-irradiation. Ascorbic acid, DL-alpha-tocopherol, butylated hydroxytoluene, and reduced glutathione were all shown to reverse UVL-induced cytotoxicity. At concentrations tested, no protective effect was detected when any of these antioxidants were added prior to UVL irradiation.